There are available today a wide variety of mobile devices, including mobile telephones, e.g., cellular telephones, personal digital assistants (PDAs), GPS devices, and so forth. Such mobile devices typically have a small form factor in order to make them more portable and/or more attractive.
Mobile devices, however, are typically restricted as to the type and number of input/output devices that may be attached. Microphones and video cameras, for example, are becoming common. Connecting to other input/outputs sources is rather restricted.
There often is a need in the art to transcribe pen strokes, for example those that occur during writing. Transcription systems are known for recording such pen strokes. Luidia, Inc., the assignee of the present invention, makes a system called eBeam that provides for recording pen strokes on a surface such as a whiteboard. Such a system is interfaced, e.g., using a USB connection, to a computer and captures the pen strokes on the computer, including the color of the pen and any erasing. See for example, TechTV's online review of the eBeam system available (September 2003) at http://www.techtv.com/ as the URL http://www.techtv.com/products/hardware/story/0,23008,3376062,00.html and also as the URL http://www.techtv.com/products/print/0,23102,3376062,00.html. Such a system is useful for capturing pen strokes on a whiteboard, or even on a flip chart. While typically, a computer is used, the device may be interfaced to a PDA. A similar recording device also is known that is battery operated and that records pen strokes without a computer. The stored pen strokes do, at some stage, need to be loaded to a computer. See, for example, the Mimio XI® device made by Virtual Ink Corporation of Boston, Mass.
So while devices that capture pen strokes are known, there is however, a need for a device that can capture pen strokes on a small scale, for example, when writing on a letter-size sheet of paper. While digitizing pads are known that provide for such pen stroke capturing, such digitizing pads are relatively bulky and non-portable. Furthermore, such digitizing pads need to be interfaced to a computer, or are incorporated in a computer.
Thus there is a need for a device that can capture pen strokes, e.g., on a sheet of paper, and that is portable.
It is known to project a computer-generated image on a flat surface. It also is known to project such a computer generated image on to a surface such as a white board, and to then capture pen strokes drawn on the projected image, e.g., as an overlay. The above-mentioned eBeam system can transform any flat surface into an area wherein pen strokes are capturable. One or more computer generated images may be projected on such a surface, e.g., using a common LCD projector attached to the video output port of a computer, e.g., a laptop computer. Using the eBeam system, pen strokes drawn over the projected image may be captured for later playback and analysis, including synchronized playback with the projected image or images. Such an arrangement is however bulky, and suitable for when there is a large enough audience.
It also is known to use a computer display such as a LCD display that has a touch. sensitive surface, or onto which is retrofitted a pen stroke capture system such as an eBeam system. Such a device, however, requires a laptop computer or a tablet computer, and further requires drawing on a screen or similar surface.
There thus is a need for a portable system that can project an image onto a relatively small area and that incorporates a pen-location system for capturing pen strokes.